3d motion correction using 3d deformable registration and patient respiratory signals

ABSTRACT

Embodiments can provide a computer-implemented method for 3D motion correction for diffusion weighted imaging images, the method comprising acquiring a series of image slices from a medical imaging device; binning the series of image slices into bins, each bin comprising a plurality of slice locations; identifying, for each of the B-values, a dominating breathing state wherein at least one of the plurality of slice locations of the dominating breathing state contains an image slice from the series of images; identifying, for each of the B-values, one or more non-dominating breathing states; and registering, for each of the B-values, all of the one or more non-dominating breathing states to the dominating breathing state.

TECHNOLOGY FIELD

This application claims the benefit of U.S. Provisional Application Ser.No. 62/399,703 filed Sep. 26, 2016, which is incorporated herein byreference in its entirety.

The present invention relates generally to methods, systems, andapparatuses for utilizing patient respiratory signals and 3D deformableregistration in order to provide three-dimensional motion correction fortwo-dimensional acquisition based (Magnetic Resonance) MR sequences,such as diffusion weighted imaging.

BACKGROUND

Respiratory motion management is a common challenge for many MR thoracicand abdominal applications. A breath-hold is typically 10-20 seconds,however most MR measurement sequences take much longer to complete.Therefore, motion needs to be carefully controlled in such applicationsfor diagnostic quality imaging. In the case of diffusion weightedimaging (DWI) the acquisition of a single image is relatively fastcompared to a breathing cycle, however the signal to noise ratio of asingle acquisition is typically too low for diagnosis. While averagingmultiple acquisitions can effectively improve signal to noise ratio,critical structure edges are also blurred if significant motion ispresent during the acquisition.

For clinically desired image quality, respiratory triggered MR sequencesare used as the current state-of-art approaches to address the motionbeside simple averaging with the associated loss in sharpness. Triggeredacquisitions come at the expense of extended scan time. Furthermoretriggering requires an additional hardware device such as a respiratorybelt or additional acquisition modules. For instance, Siemens MagnetomTrio provides the Physiological Measurement Unit (PMU) as an option tocontrol MR sequence using a patient's physiological signal, includingrespiration.

SUMMARY

Embodiments can provide a computer-implemented method for 3D motioncorrection for diffusion weighted imaging images, the method comprisingacquiring a series of image slices from a medical imaging device;binning the series of image slices into bins based on breathing state,each bin comprising a plurality of slice locations; identifying, foreach of the B-values, a dominating breathing state wherein at least oneof the plurality of slice locations of the dominating breathing statecontains an image slice from the series of images; identifying, for eachof the B-values, one or more non-dominating breathing states; andregistering, for each of the B-values, all of the one or morenon-dominating breathing states to the dominating breathing state.

Embodiments can further provide a method further comprising if less thanall of the plurality of slice locations of the dominating breathingstate contain an image slice from the series of image slices,interpolating one or more additional images into the one or more emptyslice locations.

Embodiments can further provide a method further comprising if less thanall of the plurality of slice locations of the dominating breathingstate contain an image slice from the series of image slices,interpolating one or more additional images taken from the one or morenon-dominating breathing states into the one or more empty slicelocations.

Embodiments can further provide a method further comprising identifyinga breathing state for each of the images in the series of images using aphysiological monitoring unit value measured at the time each of theimages is acquired.

Embodiments can further provide a method further comprising registeringeach of the image slices in the series of image slices to a motion-freereference space.

Embodiments can further provide a method wherein the motion-freereference space is the dominating breathing state.

Embodiments can further provide a method further comprising calculatinga correlation of one or more motion states between the image slicesacquired during a time period.

In another illustrative embodiment, a non-transitory computer programproduct comprising a computer usable or readable medium having acomputer readable program is provided. The computer readable program,when executed on a processor, causes the processor to perform variousones of, and combinations of, the operations outlined above with regardto the method illustrative embodiment.

In yet another illustrative embodiment, a system is provided. The systemmay comprise a medical imaging device comprising an imaging processorconfigured to perform various ones of, and combinations of, theoperations outlined above with regard to the method illustrativeembodiment.

Additional features and advantages of the invention will be madeapparent from the following detailed description of illustrativeembodiments that proceeds with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other aspects of the present invention are bestunderstood from the following detailed description when read inconnection with the accompanying drawings. For the purpose ofillustrating the invention, there is shown in the drawings embodimentsthat are presently preferred, it being understood, however, that theinvention is not limited to the specific instrumentalities disclosed.Included in the drawings are the following Figures:

FIG. 1 shows a medical imaging device for acquiring diffusion weightedimages, as used by some embodiments of the present invention;

FIG. 2 illustrates a sample ideal two-dimensional (2D) MR acquisitionsequence;

FIG. 3 illustrates a flowchart depicting the functionality of the motioncorrection system, in accordance with embodiments discussed herein;

FIG. 4 illustrates the identification of a dominating breathing state,in accordance with embodiments discussed herein;

FIG. 5 illustrates registration of non-dominating breathing states todominating breathing states within and between B-values, in accordancewith embodiments discussed herein; and

FIG. 6 illustrates an exemplary computing environment within whichembodiments of the invention may be implemented.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The following disclosure describes the present invention according toseveral embodiments directed at methods, systems, and apparatusesrelated to using three dimensional deformable registration and patientrespiratory data as methods for three dimensional motion correction intwo dimensional acquisition methods. In this invention, a method tocompensate motion artifacts in different acquisitions using respiratorysignal values from physiological monitoring unit (PMU) can be used.Based on PMU values, the dominating breathing state can be identified,and then all the other acquisitions can be warped to this dominatingbreathing state for motion-free DWI acquisitions of all B-values andslice locations. The invention can target the 2D acquisition based MRsequences, like DWI. During such acquisitions, 2D images can berepeatedly acquired at certain locations over time. The breathing statefor each image can be identified by the PMU value measured together withthe image, if PMU signals are available.

FIG. 1 shows a medical imaging device 100 for acquiring diffusionweighted images, as used by some embodiments of the present invention.In medical imaging device 100, magnetic coils 12 create a static basemagnetic field in the body of patient 11 to be imaged and positioned ona table. Within the magnet system are gradient coils 14 for producingposition dependent magnetic field gradients superimposed on the staticmagnetic field. Gradient coils 14, in response to gradient signalssupplied thereto by a gradient and shim coil control module 16, produceposition dependent and shimmed magnetic field gradients in threeorthogonal directions and generates magnetic field pulse sequences. Theshimmed gradients compensate for inhomogeneity and variability in aMagnetic Resonance Imaging (MRI) device magnetic field resulting frompatient anatomical variation and other sources. The magnetic fieldgradients include a slice-selection gradient magnetic field, aphase-encoding gradient magnetic field and a readout gradient magneticfield that are applied to patient 11.

Further Radio Frequency (RF) module 20 provides RF pulse signals to RFcoil 18, which in response produces magnetic field pulses which rotatethe spins of the protons in the imaged body of the patient 11 by ninetydegrees or by one hundred and eighty degrees for so-called “spin echo”imaging, or by angles less than or equal to 90 degrees for so-called“gradient echo” imaging. Gradient and shim coil control module 16 inconjunction with RF module 20, as directed by central control unit 26,control slice-selection, phase-encoding, readout gradient magneticfields, radio frequency transmission, and magnetic resonance signaldetection, to acquire magnetic resonance signals representing planarslices of patient 11.

In response to applied RF pulse signals, the RF coil 18 receivesmagnetic resonance signals, i.e., signals from the excited protonswithin the body as they return to an equilibrium position established bythe static and gradient magnetic fields. The magnetic resonance signalsare detected and processed by a detector within RF module 20 and k-spacecomponent processor unit 34 to provide a magnetic resonance dataset toan image data processor for processing into an image. In someembodiments, the image data processor is located in central control unit26. However, in other embodiments such as the one depicted in FIG. 1,the image data processor is located in a separate unit 27.Electrocardiography (ECG) synchronization signal generator 30 providesECG signals used for pulse sequence and imaging synchronization. A twoor three dimensional k-space storage array of individual data elementsin k-space component processor unit 34 stores corresponding individualfrequency components comprising a magnetic resonance dataset. Thek-space array of individual data elements has a designated center andindividual data elements individually have a radius to the designatedcenter.

A magnetic field generator (comprising coils 12, 14, and 18) generates amagnetic field for use in acquiring multiple individual frequencycomponents corresponding to individual data elements in the storagearray. The individual frequency components are successively acquired inan order in which the radius of respective corresponding individual dataelements increases and decreases along a substantially spiral path asthe multiple individual frequency components are sequentially acquiredduring acquisition of a magnetic resonance dataset representing amagnetic resonance image. A storage processor in the k-space componentprocessor unit 34 stores individual frequency components acquired usingthe magnetic field in corresponding individual data elements in thearray. The radius of respective corresponding individual data elementsalternately increases and decreases as multiple sequential individualfrequency components are acquired. The magnetic field acquiresindividual frequency components in an order corresponding to a sequenceof substantially adjacent individual data elements in the array andmagnetic field gradient change between successively acquired frequencycomponents which are substantially minimized.

Central control unit 26 uses information stored in an internal databaseto process the detected magnetic resonance signals in a coordinatedmanner to generate high quality images of a selected slice(s) of thebody (e.g., using the image data processor) and adjusts other parametersof medical imaging device 100. The stored information comprisespredetermined pulse sequence and magnetic field gradient and strengthdata as well as data indicating timing, orientation and spatial volumeof gradient magnetic fields to be applied in imaging. Generated imagesare presented on display 40 of the operator interface. Computer 28 ofthe operator interface includes a graphical user interface (GUI)enabling user interaction with central control unit 26 and enables usermodification of magnetic resonance imaging signals in substantially realtime. Continuing with reference to FIG. 1, display processor 37processes the magnetic resonance signals to reconstruct one or moreimages for presentation on display 40, for example. Various techniquesgenerally known in the art may be used for reconstruction. Aphysiological monitoring unit (PMU) 42 can be used to monitorphysiological signals that emanate from the patient 11, including, butnot limited to, respiration, heartrate, blood pressure, and pulseoximetry.

FIG. 2 illustrates a sample ideal two-dimensional (2D) MR acquisitionsequence. During such an acquisition, 2D images 200 can be repeatedlyacquired at certain bodily locations (or slice locations 201) over a setperiod of time 202. The breathing state for each image can be identifiedby the physiological monitoring unit (PMU) 42 (as shown in FIG. 1) valuemeasured together with the image 200 in relation to the time 202 theimage was taken. In an embodiment, PMU signals may not be available.Breathing states can be organized according to bins.

FIG. 3 illustrates a flowchart depicting the functionality of the motioncorrection system, in accordance with embodiments discussed herein. Themotion correction system can function using three major states. First,the system can identify a dominating breathing state 301. The dominatingbreathing state is defined herein as the breathing state in which themost image slices are acquired. For example, FIG. 4 shows acquisitionsequence where a plurality of image slices (each labeled Image 200) areacquired over a plurality of breathing states (each labeled breathingstate 402). These breathing states may be derived, for example, from thebreathing states acquired using the respiratory signal values from thePMU 42 (as shown in FIG. 1). During the acquisition sequence, there areone or more Breathing States 402 where an image slice is not acquired(labeled No Image 201). As shown in FIG. 4, the dominating breathing 400can be determined as the Breathing State 402 with the most Image 200acquisitions, as opposed to a state where No Images 201 outweigh Images200 taken. Additionally, the dominating breathing state 400 can have allor almost all of its slice locations have at least one Image 200acquisition. The combination of these characteristics can be used tofind the dominating breathing state 400, which in turn can be used togenerate a dominating breathing state volume 401, comprising one or moreImages 200 from the dominating breathing state 400.

Returning to FIG. 3, after identifying a dominating breathing statevolumes at 301, the system can register the dominating breathing statevolumes for all B-values 302. As is generally understood in the art, theterm B-value identifies the strength and timing of the gradients used ingenerating diffusion-weighted images. For further processing, all imagescan be registered to one motion-free reference space (motion-freereference space B-value 501 as shown in FIG. 5). A particular B-valuecan be chosen as the motion-free reference space if its intensitydistribution is closest to corresponding B-value images, which canproduce more accurate registration results. In order to support furtherprocessing, such as an analog to digital conversion (ADC) mapcalculation, all acquired images can be registered to one motion-freereference space, which in this instance can be the dominating breathingstate identified previously. In an embodiment, acquisition data may notbe available for a slice location in the dominating breathing state, andmissing slices can be interpolated from neighboring slices.

The system can register all other motion states to the dominatingbreathing state at 303. Within each B-value, all non-dominatingbreathing state volumes can be registered to the dominating breathingstate volume that has already been deformed to the reference space. FIG.5 illustrates the cross B-value registration, in accordance withembodiments described herein. Images from the dominating breathing state503 of the non-motion-free reference space B-value 502 can be registeredto the dominating breathing state 504 of the motion-free reference spaceB-value 501. Non-dominating breathing states, and occasionallydominating breathing states, do not have acquisitions on every slicelocation. In this situation, the missing slices can be filled usinginterpolation 505 within the B-value to produce a dominating breathingstate 504 volume that comprises a complete set of Images 200.

In alternate embodiments, the motion state binning can also be performedbased on image contents, such as by calculating correlation of motionstates between slices that can be acquired around the same time (forinstance, by enforcing a measure that requires similar motion states insubsequent acquisitions), and by using image similarity (for instance,enforcing a strong correlation between images of the same slice in thesame motion state). In an alternate embodiment, the system can bedesigned with real-time feedback, wherein the motion state can bedetermined in real-time (for instance, through detection of theamplitude of the PMU signal), and the ordering of the acquisitions canbe adjusted such that the dominating motion state can be filled as muchas possible for each slice position.

FIG. 6 illustrates an exemplary computing environment 600 within whichembodiments of the invention may be implemented. For example, thecomputing environment 600 may be used to implement one or more of thecomponents illustrated in the medical imaging device 100 of FIG. 1. Thecomputing environment 600 may include computer system 610, which is oneexample of a computing system upon which embodiments of the inventionmay be implemented. Computers and computing environments, such ascomputer system 610 and computing environment 600, are known to those ofskill in the art and thus are described briefly here.

As shown in FIG. 6, the computer system 610 may include a communicationmechanism such as a bus 621 or other communication mechanism forcommunicating information within the computer system 610. The computersystem 610 further includes one or more processors 620 coupled with thebus 621 for processing the information. The processors 620 may includeone or more central processing units (CPUs), graphical processing units(GPUs), or any other processor known in the art.

The computer system 610 also includes a system memory 630 coupled to thebus 621 for storing information and instructions to be executed byprocessors 620. The system memory 630 may include computer readablestorage media in the form of volatile and/or nonvolatile memory, such asread only memory (ROM) 631 and/or random access memory (RAM) 632. Thesystem memory RAM 632 may include other dynamic storage device(s) (e.g.,dynamic RAM, static RAM, and synchronous DRAM). The system memory ROM631 may include other static storage device(s) (e.g., programmable ROM,erasable PROM, and electrically erasable PROM). In addition, the systemmemory 630 may be used for storing temporary variables or otherintermediate information during the execution of instructions by theprocessors 620. A basic input/output system (BIOS) 633 containing thebasic routines that help to transfer information between elements withincomputer system 610, such as during start-up, may be stored in ROM 631.RAM 632 may contain data and/or program modules that are immediatelyaccessible to and/or presently being operated on by the processors 620.System memory 630 may additionally include, for example, operatingsystem 634, application programs 635, other program modules 636 andprogram data 637.

The computer system 610 also includes a disk controller 640 coupled tothe bus 621 to control one or more storage devices for storinginformation and instructions, such as a hard disk 641 and a removablemedia drive 642 (e.g., floppy disk drive, compact disc drive, tapedrive, and/or solid state drive). The storage devices may be added tothe computer system 610 using an appropriate device interface (e.g., asmall computer system interface (SCSI), integrated device electronics(IDE), Universal Serial Bus (USB), or FireWire).

The computer system 610 may also include a display controller 665coupled to the bus 621 to control a display 666, such as a cathode raytube (CRT) or liquid crystal display (LCD), for displaying informationto a computer user. The computer system includes an input interface 660and one or more input devices, such as a keyboard 662 and a pointingdevice 661, for interacting with a computer user and providinginformation to the processor 620. The pointing device 661, for example,may be a mouse, a trackball, or a pointing stick for communicatingdirection information and command selections to the processor 620 andfor controlling cursor movement on the display 666. The display 666 mayprovide a touch screen interface which allows input to supplement orreplace the communication of direction information and commandselections by the pointing device 661.

The computer system 610 may perform a portion or all of the processingsteps of embodiments of the invention in response to the processors 620executing one or more sequences of one or more instructions contained ina memory, such as the system memory 630. Such instructions may be readinto the system memory 630 from another computer readable medium, suchas a hard disk 641 or a removable media drive 642. The hard disk 641 maycontain one or more datastores and data files used by embodiments of thepresent invention. Datastore contents and data files may be encrypted toimprove security. The processors 620 may also be employed in amulti-processing arrangement to execute the one or more sequences ofinstructions contained in system memory 630. In alternative embodiments,hard-wired circuitry may be used in place of or in combination withsoftware instructions. Thus, embodiments are not limited to any specificcombination of hardware circuitry and software.

As stated above, the computer system 610 may include at least onecomputer readable medium or memory for holding instructions programmedaccording to embodiments of the invention and for containing datastructures, tables, records, or other data described herein. The term“computer readable medium” as used herein refers to any medium thatparticipates in providing instructions to the processor 620 forexecution. A computer readable medium may take many forms including, butnot limited to, non-volatile media, volatile media, and transmissionmedia. Non-limiting examples of non-volatile media include opticaldisks, solid state drives, magnetic disks, and magneto-optical disks,such as hard disk 641 or removable media drive 642. Non-limitingexamples of volatile media include dynamic memory, such as system memory630. Non-limiting examples of transmission media include coaxial cables,copper wire, and fiber optics, including the wires that make up the bus621. Transmission media may also take the form of acoustic or lightwaves, such as those generated during radio wave and infrared datacommunications.

The computing environment 600 may further include the computer system610 operating in a networked environment using logical connections toone or more remote computers, such as remote computer 680. Remotecomputer 680 may be a personal computer (laptop or desktop), a mobiledevice, a server, a router, a network PC, a peer device or other commonnetwork node, and typically includes many or all of the elementsdescribed above relative to computer system 610. When used in anetworking environment, computer system 610 may include modem 672 forestablishing communications over a network 671, such as the Internet.Modem 672 may be connected to bus 621 via user network interface 670, orvia another appropriate mechanism.

Network 671 may be any network or system generally known in the art,including the Internet, an intranet, a local area network (LAN), a widearea network (WAN), a metropolitan area network (MAN), a directconnection or series of connections, a cellular telephone network, orany other network or medium capable of facilitating communicationbetween computer system 610 and other computers (e.g., remote computer680). The network 671 may be wired, wireless or a combination thereof.Wired connections may be implemented using Ethernet, Universal SerialBus (USB), RJ-11 or any other wired connection generally known in theart. Wireless connections may be implemented using Wi-Fi, WiMAX, andBluetooth, infrared, cellular networks, satellite or any other wirelessconnection methodology generally known in the art. Additionally, severalnetworks may work alone or in communication with each other tofacilitate communication in the network 671.

The embodiments of the present disclosure may be implemented with anycombination of hardware and software. In addition, the embodiments ofthe present disclosure may be included in an article of manufacture(e.g., one or more computer program products) having, for example,computer-readable, non-transitory media. The media has embodied therein,for instance, computer readable program code for providing andfacilitating the mechanisms of the embodiments of the presentdisclosure. The article of manufacture can be included as part of acomputer system or sold separately.

While various aspects and embodiments have been disclosed herein, otheraspects and embodiments will be apparent to those skilled in the art.The various aspects and embodiments disclosed herein are for purposes ofillustration and are not intended to be limiting, with the true scopeand spirit being indicated by the following claims.

An executable application, as used herein, comprises code or machinereadable instructions for conditioning the processor to implementpredetermined functions, such as those of an operating system, a contextdata acquisition system or other information processing system, forexample, in response to user command or input. An executable procedureis a segment of code or machine readable instruction, sub-routine, orother distinct section of code or portion of an executable applicationfor performing one or more particular processes. These processes mayinclude receiving input data and/or parameters, performing operations onreceived input data and/or performing functions in response to receivedinput parameters, and providing resulting output data and/or parameters.

A graphical user interface (GUI), as used herein, comprises one or moredisplay images, generated by a display processor and enabling userinteraction with a processor or other device and associated dataacquisition and processing functions. The GUI also includes anexecutable procedure or executable application. The executable procedureor executable application conditions the display processor to generatesignals representing the GUI display images. These signals are suppliedto a display device which displays the image for viewing by the user.The processor, under control of an executable procedure or executableapplication, manipulates the GUI display images in response to signalsreceived from the input devices. In this way, the user may interact withthe display image using the input devices, enabling user interactionwith the processor or other device.

The functions and process steps herein may be performed automatically orwholly or partially in response to user command. An activity (includinga step) performed automatically is performed in response to one or moreexecutable instructions or device operation without user directinitiation of the activity.

The system and processes of the figures are not exclusive. Othersystems, processes and menus may be derived in accordance with theprinciples of the invention to accomplish the same objectives. Althoughthis invention has been described with reference to particularembodiments, it is to be understood that the embodiments and variationsshown and described herein are for illustration purposes only.Modifications to the current design may be implemented by those skilledin the art, without departing from the scope of the invention. Asdescribed herein, the various systems, subsystems, agents, managers andprocesses can be implemented using hardware components, softwarecomponents, and/or combinations thereof. No claim element herein is tobe construed under the provisions of 35 U.S.C. 112, sixth paragraph,unless the element is expressly recited using the phrase “means for.”

We claim:
 1. A computer-implemented method for 3D motion correction fordiffusion weighted imaging images, the method comprising: acquiring aseries of image slices from a medical imaging device; binning the seriesof image slices into bins based on breathing state, each bin comprisinga plurality of slice locations; identifying, for each of one or moreB-values, a dominating breathing state wherein at least one of theplurality of slice locations of the dominating breathing state containsan image slice from the series of image slices; identifying, for each ofthe B-values, one or more non-dominating breathing states; andregistering, for each of the B-values, all of the one or morenon-dominating breathing states to the dominating breathing state. 2.The method as recited in claim 1, further comprising: if less than allof the plurality of slice locations of the dominating breathing statecontain an image slice from the series of image slices, interpolatingone or more additional images into one or more empty slice locations. 3.The method as recited in claim 2, further comprising: if less than allof the plurality of slice locations of the dominating breathing statecontain an image slice from the series of image slices, interpolatingone or more additional images taken from the one or more non-dominatingbreathing states into the one or more empty slice locations.
 4. Themethod as recited in claim 1, further comprising: identifying abreathing state for each of the images in the series of image slicesusing a physiological monitoring unit value measured at the time each ofthe images is acquired.
 5. The method as recited in claim 1, furthercomprising: registering each of the image slices in the series of imageslices to a motion-free reference space.
 6. The method as recited inclaim 5, wherein the motion-free reference space is the dominatingbreathing state.
 7. The method as recited in claim 1, furthercomprising: calculating a correlation of one or more motion statesbetween the image slices acquired during a time period.
 8. A computerprogram product for 3D motion correction for diffusion weighted imagingimages, the computer program product comprising a non-transitorycomputer readable storage medium having program instructions embodiedtherewith, the program instructions executable by a processor to causethe processor to: acquire a series of image slices from a medicalimaging device; bin the series of image slices into bins based onbreathing state, each bin comprising a plurality of slice locations;identify, for each of one or more B-values, a dominating breathing statewherein at least one of the plurality of slice locations of thedominating breathing state contains an image slice from the series ofimage slices; identify, for each of the B-values, one or morenon-dominating breathing states; and register, for each of the B-values,all of the one or more non-dominating breathing states to the dominatingbreathing state.
 9. The computer program product as recited in claim 8,wherein the processor is further caused to: if less than all of theplurality of slice locations of the dominating breathing state containan image slice from the series of image slices, interpolate one or moreadditional images into one or more empty slice locations.
 10. Thecomputer program product as recited in claim 9, wherein the processor isfurther caused to: if less than all of the plurality of slice locationsof the dominating breathing state contain an image slice from the seriesof image slices, interpolate one or more additional images taken fromthe one or more non-dominating breathing states into the one or moreempty slice locations.
 11. The computer program product as recited inclaim 8, wherein the processor is further caused to: identify abreathing state for each of the images in the series of image slicesusing a physiological monitoring unit value measured at the time each ofthe images is acquired.
 12. The computer program product as recited inclaim 8, wherein the processor is further caused to: register each ofthe image slices in the series of image slices to a motion-freereference space.
 13. The computer program product as recited in claim12, wherein the motion-free reference space is the dominating breathingstate.
 14. The computer program product as recited in claim 8, whereinthe processor is further caused to: calculate a correlation of one ormore motion states between the image slices acquired during a timeperiod.
 15. A system for 3D motion correction for diffusion weightedimaging images, the system comprising: a medical imaging devicecomprising a physiological monitoring unit and an image data processorconfigured to: acquire a series of image slices from the medical imagingdevice; bin the series of image slices into bins based on breathingstate, each bin comprising a plurality of slice locations; identify, foreach of one or more B-values, a dominating breathing state wherein atleast one of the plurality of slice locations of the dominatingbreathing state contains an image slice from the series of image slices;identify, for each of the B-values, one or more non-dominating breathingstates; and register, for each of the B-values, all of the one or morenon-dominating breathing states to the dominating breathing state. 16.The system as recited in claim 15, wherein the image data processor isfurther configured to: if less than all of the plurality of slicelocations of the dominating breathing state contain an image slice fromthe series of image slices, interpolate one or more additional imagesinto one or more empty slice locations.
 17. The system as recited inclaim 16, wherein the image data processor is further configured to: ifless than all of the plurality of slice locations of the dominatingbreathing state contain an image slice from the series of image slices,interpolate one or more additional images taken from the one or morenon-dominating breathing states into the one or more empty slicelocations.
 18. The system as recited in claim 15, wherein the image dataprocessor is further configured to: identify a breathing state for eachof the images in the series of images using a physiological monitoringunit value measured from the physiological monitoring unit at the timeeach of the image slices is acquired.
 19. The system as recited in claim15, wherein the image data processor is further configured to: registereach of the image slices in the series of image slices to a motion-freereference space.
 20. The system as recited in claim 15, wherein theimage data processor is further configured to: calculate a correlationof one or more motion states between the image slices acquired during atime period.